Topical Magnesium Sulfate Versus Peritonsillar Bupivacaine for Post-Tonsillectomy Pain Relief in Children

Overview

Tonsillectomy (tonsil removal) is a very common surgery for children, but it often causes significant throat and ear pain afterward. Doctors usually inject a numbing medicine, such as bupivacaine, into the area around the tonsils to help control this pain. However, these injections require needles, which can cause swelling, distort tissue, and slightly increase the risk of bleeding or infection, and the pain relief typically only lasts for about 4 to 6 hours. This study is investigating a needle-free alternative to see if it provides effective pain relief. The researchers are testing a medication called magnesium sulfate, which blocks certain pain receptors and can be applied directly to the surgical site using a soaked gauze pad instead of a needle injection. The main goal of this clinical trial is to compare how well topical magnesium sulfate relieves pain compared to standard bupivacaine injections in children undergoing tonsillectomy. The study will include 40 children between the ages of 8 and 15 years old. During the surgery, while under general anesthesia, half of the children will receive the topical magnesium sulfate pad applied to the surgical area for 5 minutes, and the other half will receive the standard bupivacaine injection. After the surgery, researchers will measure the children's pain levels using visual pain scales featuring faces and numbers. They will also track how much extra pain medication the children need, how well their surgical wounds heal, and if they experience any adverse effects.

Postoperative pain following tonsillectomy is a primary cause of morbidity in the pediatric population, frequently leading to "tonsillectomy distress syndrome," which is characterized by severe odynophagia, referred otalgia, and psychological distress. The underlying pathophysiology of this pain is complex, involving both mechanical trauma to the pharyngeal constrictor muscles and the chemical irritation of the vagus and glossopharyngeal nerve endings. While perioperative analgesia is traditionally managed with local anesthetic infiltration, such as bupivacaine, its analgesic efficacy is typically limited to a short duration of 4 to 6 hours. Furthermore, the physical act of needle infiltration can induce tissue edema, distort surgical planes, and potentially elevate the risk of postoperative complications, including infection and hemorrhage. Recent advancements in pain management have highlighted the role of N-methyl-D-aspartate (NMDA) receptors in peripheral tissues, presenting new avenues for non-invasive analgesia. Magnesium sulfate serves as an NMDA receptor antagonist by blocking its calcium channel in a voltage-dependent manner. This trial investigates whether applying magnesium sulfate topically to the tonsillar fossa can provide effective postoperative analgesia without the inherent risks associated with needle infiltration. To ensure procedural standardization across the study, all tonsillectomies in this prospective, randomized trial will be performed utilizing a cold dissection technique under general anesthesia. Postoperatively, patients will be systematically evaluated to assess pain intensity, mucosal healing via a 5-point fibrin and epithelialization grading scale, and the overall requirement for rescue analgesics.